Perhaps someone has the answer to this question,...at what point does a hybrid become a a Mallard in your daily bag ?Is there one key feature that tips the scale to call it a Mallard rather than a Black. (speaking mostly of drakes, as this is where to conversion is most evident)I've never shot one that I thought might go either way, but I was scouting down on the south coast yesterday and an awful lot of the blacks were looking pretty green in the head, yellow-ish bills, etc. Several of them looked a lot like drake widgeons, if only they would have had blue bills. Please let me know if you have an opinion or know the answer, it would be a good argument to make should the game warden start checking DNA results on the dead ducks in my boat !

I always default to the "Dominant Trait" If it looks mostly like a black duck then chances are the EPO or federal warden will count it as such. According to the USFWS biologist, Green on the head of a black duck is fairly common and is not considered a hybrid trait.

Thanks for the reply Mike, that is what I would differ to, the 'more than 50%' of a particular species rule should apply.

I disagree with the biologist however, as I think that an abundance of green in the head and any influence of yellow in the bill are most definitely Hybrid traits. Unfortunately the true American Black Duck may become a lost species as inter-breeding with Mallards will become more and more prevelant.

I have always gone by the white bar above the speculum. As far as identifying in flight, I usually assume its a black in flight unless it is very easily identifiable as a black duck (considering I hunt salt marshes I always side with assuming it is a black duck). Here is a credible source and somewhat helpful study although it only talks about the wing plumage